Disorganization of Retinal Inner Layers Linked to Visual Acuity Prognoses

Rishi P. Singh, MD

New research suggests disorganization of retinal inner layers (DRIL) could be a biomarker for visual acuity and treatment prognosis among patients with retinal vein occlusion (RVO).

The findings are based on a retrospective study of 147 patients with treatment-naive branch RVO (BRVO), central RVO (CRVO), or hemispheric RVO (HRVO).

In an analysis of patient data, researchers from the Cleveland Clinic, Case Western Reserve University, and the Federal University of Sao Paolo, Brazil, found baseline DRIL assessments were correlated to visual acuity outcomes. They also found that changes to DRIL after anti—vascular endothelial growth factor (AVF) therapy for macular edema secondary to RVO could be a biomarker for improvement in visual acuity.

The study is the latest effort to probe how structural changes can be important biomarkers in ophthalmological conditions.

“We have seen DRIL be an important marker in diabetic retinopathy and diabetic macular edema,” Rishi P. Singh, MD, of the Cleveland Clinic, told MD Magazine®. “We currently lack good indicators for visual improvement.”

In 2014, a different team of researchers performed a similar study looking at patients with diabetic macular edema (DME). In that study, 96 patients with DME were given spectral domain-optical coherence tomography (SD-OCT) at baseline, 4 months, and 8 months. DRIL scores were then judged against visual acuity scores.

Worse DRIL was tied to worse visual acuity at baseline. And patients whose DRIL had worsened at 4 months had worse visual acuity at the eight-month checkup.

“Disorganization of the retinal inner layers in the 1-mm foveal area is associated with VA, and change in DRIL predicts future change in VA,” noted first author Jennifer Katherine Sun, MD, of Harvard Medical School, and colleagues. “Early change in DRIL prospectively identifies eyes with a high likelihood of subsequent VA improvement or decline.”

Investigators also suggested further research was needed to confirm and better define the phenomenon. In the new study, Singh and colleagues pick up the torch.

The researchers looked for patients over the age of 18 who visited a tertiary eye care clinic between December 2010 and January 2016. Patients with confounding retinal or ocular disease, history of pars plana vitrectomy, or prior intravitreal injections were excluded. They were given DRIL scores by 2 masked graders, with a third grader available in cases of discrepancies. DRIL scores were made at baseline, and at 6 months and 12 months using SD-OCT.

Six in 10 patients (61.9%; 91 patients) had evidence of DRIL at baseline. Patients in that group who had been diagnosed with BRVO had a lower visual acuity score at baseline, though the same correlation was not seen in patients with CRVO.

Patients with CRVO/HRVO who did not have DRIL at baseline reported greater gains in visual acuity after 6 months of AVF therapy. Meanwhile, patients in the CRVO/HRVO group who had increasing DRIL scores had lower improvement in visual acuity scores at both 6 and 12 months.

BRVO patients with continued DRIL had lower visual acuity gains at 6 months.

Singh said the new research should give physicians better answers to explain outcome disparities.

“We know that our anti-VEGF medications work in many patients but their outcomes might be drastically different,” he said. “So this allows us to better inform the patient and in addition inform the doctor that the patient might have a poor prognosis for vision recovery.”

The study, “Association of Disorganization of Retinal Inner Layers With Visual Acuity Response to Anti—Vascular Endothelial Growth Factor Therapy for Macular Edema Secondary to Retinal Vein Occlusion,” was published online in JAMA Ophthalmology.